Boron Isotope Ratio Analysis and Quantification at the Sub-Nanogram Scale Using Isotope Dilution and Total Evaporation Method via Negative Thermal Ionization Mass Spectrometry

Abstract

We developed a highly sensitive method for precise boron isotope ratio analysis and quantification at the sub-nanogram level using isotope dilution-total evaporation (ID-TE) combined with negative thermal ionization mass spectrometry (NTI-MS). Boron isotope ratios were measured by detecting BO2- ions with a TRITON NTI-MS, yielding results consistent with certified standards and excellent reproducibility (RSD = 0.44%, n = 24). Strong correlations confirmed the accuracy of this method, which demonstrated a detection limit of 0.09 pg. This approach shows great potential for accurate boron isotope and concentration analyses in geological, biological, environmental, and nuclear-related samples.